The objective is to develop a rechargeable battery that is small enough to be incorporated in an ITC device, will contain adequate power to operate a hearing aid reliably for at least one day, can be readily recharged at night and will last for the life time of the hearing aid. The hearing aid will normally be placed into a charger receptacle each evening, to be fully recharged within six hours. A lithium-ion battery chemistry provides the basis for this high voltage, rechargeable cell that is safe and contains no lithium metal. The battery design and process development will be completed during the first 18 months. In collaboration with an existing battery manufacturer, a pilot line will be established for the production of qualification batteries. In parallel, a compact recharging system will be developed. Two alternatives will be evaluated. A consortium of hearing aid manufacturers will be established to guide development and facilitate commercialization. PROPOSED COMMERCIAL APPLICATION: Approximately 5 million people in the U.S. wear hearing aids. With battery replacement required every 1-2 weeks, over 150 million batteries are consumed annually; a battery cost in excess of $150 million. Annualized user costs for a rechargeable battery are estimated at $85 million. This represents a potential savings in health care costs of $65 million, while providing improved therapy and reduced hazards.